1. Field of the Invention
This invention relates to a recording or reproducing apparatus.
2. Description of the Related Art
Recording or reproducing apparatuses of the kind using a rotary magnetic disc for recording or reproducing video, audio and data signals have been known.
The apparatus of this kind uses a stabilizing plate which is opposed to a recording or reproducing magnetic head across a rotating magnetic disc for the purpose of stably and adequately keeping a contact state (head touch) between the magnetic head and the magnetic disc.
This stabilizing plate is well known requiring no detailed description. Briefly stated, the plate is arranged to control the atmospheric pressure and an air flow taking place near the head in such a way as to prevent the magnetic disc from buoying up or vibrating relative to the magnetic head. Apparatuses of the kind using the stabilizing plates have been disclosed, for example, in U.S. patent applications Ser. No. 648,701 (filed on Sep. 7, 1984), No. 648,700 (filed on Sep. 7, 1984), No. 707,871 (filed on Mar. 4, 1985), No. 777,235 (filed on Sep. 18, 1985), No. 777,282 (Filed on Sep. 18, 1985), No. 778,390 (filed on Sep. 20, 1985) and No. 838,901 (filed on Mar. 12, 1986); and U.S. Pat. Nos. 4,716,477, 4,736,357, 4,734,809, etc.
The stabilizing plate is required to control the subtle magnetic head contacting state of the magnetic disc. The operating position of the stabilizing plate, therefore, must be highly accurately determined. To meet this requirement, the stabilizing plate is provided with some positioning means for setting it in its operating position. The magnetic disc contacting position of the stabilizing plate is determined by the positioning means.
Meanwhile, a high degree of precision is also required for determining the loading position of the magnetic disc. Generally, the apparatus is provided with a positioning post for this purpose. A positioning hole provided in a magnetic disc housing jacket is fitted on this positioning post.
In accordance with the above-stated arrangement of the conventional apparatus, however, the positioning means for setting the stabilizing plate in its operating position and another positioning means for setting the magnetic disc in its loading position are arranged separately from each other. This makes the internal arrangement of the apparatus complex. Further, since the magnetic disc and the stabilizing plate are arranged to be indirectly positioned through the chassis or the like of the apparatus, their positions tend to deviate causing errors. Therefore, it has been difficult to secure an adequate degree of positioning precision.